Eremaeozetes malleensis Reticulatus E. darwinensis Reticulatus E. undulatus Mahunka, 1985 E. acutus Covarrubias, 1967 E. roguini Mahunka, 1998 New eremaeozetid mites (Acari: Oribatida: Eremaeozetoidea) from the south-western Pacific region and the taxonomic status of the Eremaeozetidae and Idiozetidae Colloff, Matthew J. Zootaxa 2012 3435 1 39 8TCSK [151,451,1677,1703] Arachnida Eremaeozetidae Eremaeozetes Animalia Sarcoptiformes 9 10 Arthropoda species malleensis sp. nov.   Female. Cerotegument: amorphous, thin, granular, complete dorsally, sparser ventrally, covered in organic and mineral debris.  Prodorsum: Lamellae relatively narrow, not extending laterally beyond margins of bothridia, fused posteriomedially, striated on posteriolateral margins, otherwise smooth, separated along anterior third by narrow median slit with parallel margins. Lamellar cuspides slightly curved medioventrally, broadly separated apically. Posteriolateral lamellar margins transverse, incised ( Fig. 5a). Rostral seta ( ro) thin, minute (3 μm long), emerging from squat tubercle ( Fig. 5b). Lamellar seta ( le) 4 μm long, spiniform, emerging from squat tubercle on apex of lamella. Bothridial seta 59 μm long; head narrow, club-shaped, barbed. Bothridium prominent, broad, cup-shaped, rim undulating.   FIGURE 5.  Eremaeozetes malleensis  sp. nov., holotype female, cerotegument removed; a) dorsal; b) ventral; c) lateral aspect.   FIGURE 6.  Eremaeozetes malleensis  sp. nov., left legs, antiaxial view, cerotegument removed; a) Leg I; b) Leg II; c) leg III; d) Leg IV.  Notogaster: Length 421 μm; ratio of length to breadth 1.37; notogaster broad, U-shaped; broadest in region of pteromorphs. Dorsosejugal suture concave becoming acute medially; median projection entire, extending to bothridia, overhanging prodorsum ( Fig. 5a). Dorsosejugal lobe triangular, broader than long, extending anteriorly as far as bothridium, medial margin straight. Lenticulus immediately posterior of apex of median projection of dorsosejugal suture, 41 μm long, 34 μm broad, ovoid, broadest basally, with discrete, simple margin. With faint elongate foveolae; faint, paired undulating longitudinal ridges, converging medially posterior of setae lp. Ten pairs of smooth, short (8–14 μm) spiniform setae on squat tubercles. Lyrifissure ihlongitudinal, 22 μm long, positioned lateral of seta lm. Caudal region of notogaster rounded, with tubercles of hand pseries projecting beyond margin.  Subcapitulum: Mentum U-shaped, as long as broad; anterior margin slightly reflexed; region immediately posterior of margin concave, smooth ( Fig. 5b). Central region of mentum with sinuous, interdigitating ridges. Seta h17 μm long, m11 μm.  Coxisternum: Epimeral setae short, sub-equal (6–8 μm long), spiniform, formula 3-1-2-2 ( Fig. 5b). Pre-genital sclerite trapezoid, with undulating margins, bearing seta 3a. Genital and anal plates separated by distance of three quarters length of genital plate. Genital plates sub-hexagonal, smooth; each plate 87 μm long, 45 μm broad, with six setae; g1 lateral of g2-6; g2 longer than others; g1 and g3-5 with bacilliform cerotegument. Aggenital seta thin, spiniform, 6 μm long, positioned posteriolateral of genital plate. Ventral plate striate posteriolaterally, otherwise smooth.  Anogenital Region: Anal plates sub-hexagonal ( Fig. 5b); each anal plate 66 μm long, 30 μm broad, smooth. Anal setae spiniform, 5 μm long. Adanal setae spiniform; ad1-2 positioned on ridge immediately posterior of anal plates; distance between ad1 and ad2 three times mutual distance between ad1; ad3 positioned laterally.   FIGURE 7.  Eremaeozetes malleensis  sp. nov., tritonymph, cerotegument removed; a) dorsal; b) ventral.  Lateral aspect: Rostrum curved, acute apically, with distinct anterior projection marked by transverse ridge dorsal of insertions of rostral setae ( Fig. 5c). Rostral seta minute, spiniform, on squat tubercle some distance from apex of rostrum. Tutorium narrow, fused apically with rostrum – without free apices. Lamellar cuspides curved anterioventrally, pointed apically, not reflexed; lamellae curved, free of prodorsum for 0.6 of entire length, with posterior septum connecting with tutorium ventrally. Lamellar setae minute, spiniform, just posterior of apex of lamellar cusp. Lamellae smooth; pedotectum I smooth, curved, lacking tooth. Interbothridial region flat. Lenticulus bulbous, curved, projecting above dorsal surface. Dorsosejugal lobe not extending as far as bothridium; pteromorph triangular, narrow, pointed, curved, smooth, extending almost as far as ventral surface, 134 μm long, 59 μm broad basally; posterior margin undulating. Centrodorsal region of notogaster flat from posterior of lenticulus to level with seta lp; posterior notogaster between lpand p1 curved, convex.  Legs: Pretarsi heterotridactylous ( Fig. 6). Formulae: Leg I: 0-4-2(1)-4(2)-16(2); Leg II 0-4-3(1)-4(1)-15(2); Leg III 0-2-2(1)-4(1)-12; Leg IV 1-2-2(1)-3(1)-11.  Tritonymph.Length 482 μm, breadth 306 μm. Prodorsum: Rostral seta ( ro) straight, smooth, 21 μm long, on short cylindrical apophysis ( Fig. 7a). Lamellar seta ( le) 25 μm long, with club-shaped tuberculate cerotegument. Interlamellar seta ( in) with club-shaped tuberculate cerotegument, 20 μm long. Bothridial seta ( bs) 48 μm long, with club-shaped, tuberculate head. Prodorsum smooth, with complex series of longitudinal and transverse ridges.  Gastronotic Region: Length 315 μm; ratio of length to breadth 1.04; U-shaped ( Fig. 7b). Cuticle with sparse, broadly-spaced plicate ridges. With 15 pairs of setae 25–44 μm long; all except pseries with club-shaped tuberculate cerotegument; pseries positioned ventrally; lseries positioned along lateral margin.   FIGURE 8.  Eremaeozetes malleensis  sp. nov., tritonymph, left legs, antiaxial view, cerotegument removed; a) Leg I; b) Leg II; c) leg III; d) Leg IV.  Coxisternum: Epimeral plates separated along sternal line by transversely-ridged cuticle ( Fig. 7b). Epimeral setal formula 3-0-1-1. Epimeral setae smooth, setiform, 8–14 μm long. Epimeral plates smooth.  Anogenital Region: Each genital plate 61 μm long, 15 μm broad, with six smooth, setiform setae, 7 μm long ( Fig. 7b). Genital plates surrounded by longitudinal and transverse striate cuticle. Each anal plate 83 μm long, 14 μm broad, smooth. Setae of pseries spiniform, smooth, 12–18 μm long, p2-3 straight, p1 curved.  Legs: Pretarsi monodactylous ( Fig. 8). Formulae: Leg I: 0-4-2(1)-4(2)-13(2); Leg II 0-3-3(1)-4(1)-12(2); Leg III 0-2-2(1)-3(1)-13; Leg IV 1-2-2-3(1)-12.   Material examined. Holotypemale, gutter of flight intercept trap, Mallee eucalypt woodland on dune-swale system, Bookmark Biosphere Reserve, 31 kmN.W. of Renmark, South Australia, 33°59'S, 140°30'E, ca.  45 m., coll. K.R. Pullen, 30 Mar.–2 May, 1995. Paratypemale and paratypetritonymph, gutter of flight intercept trap,  Casuarinaand Mallee eucalypt woodland, Bookmark Biosphere Reserve, 79 kmN.N.W. Renmark, South Australia, 33°31'S, 140°24'E, ca.  80 m., coll. K.R. Pullen, 29 Mar.–3 May, 1995. Four paratypefemales and one paratypemale, gutter of flight intercept trap, Mallee eucalypt woodland on dune-swale system, 14 kmW.N.W. Renmark, South Australia, 34°07'S 140°37'E., ca.  30 m., coll. K.R. Pullen, 28 Feb.–28 Mar.and 6 May–7 June, 1995. Holotypeand paratypesdeposited in the Australian National Insect Collection, CSIROEcosystem Sciences, Canberra.   Etymology.This species is named for its habitation of Mallee eucalypt woodland.   Remarks.The association of the tritonymph with the adult is based on their presence in the same sample; the thin, elongate shape of the bothridial seta and the setation of the legs, with the solenidia on tibia I emerging from a long apical apophysis, with φ 2 inthe dorsal position. The tritonymph has setae inand the full complement of dorsal setae ( da, dmand dp), absent in the adult.   Eremaeozetes malleensisdiffers from other species in the genus by the following combination of characters: 1) the narrow lamellae, not extending laterally beyond the margins of the bothridia; 2) the acute dorsosejugal suture overhanging the prodorsum; 3) the ovoid lenticulus, broadest basally; 4) the faint, elongate foveolae on the notogaster; 5) the faint, paired, undulating longitudinal ridges, converging medially posterior of setae lp; 6) the apically acute rostrum in lateral view, with a distinct anterior projection; 7) the narrow pteromorph in lateral view, with an undulating posterior margin; 8) the heterotridactylous pretarsus.    Eremaeozetes malleensisis a member of the Reticulatusspecies group. It is morphologically most similar to  E. darwinensisin that it has basically the same pattern of notogastral ridges, though they are much fainter, and it is heterotridactylous. Other species morphologically allied to the Reticulatusgroup but which lack well defined dorsal ridges include  E. undulatus Mahunka, 1985from St. Lucia(of unknown dactylous configuration),  E. acutus Covarrubias, 1967from Chile(which is heterotridactylous) and  E. roguini Mahunka, 1998from St. Lucia(which is monodactylous).